Data acquisition, storage and display system

ABSTRACT

Medical data including temperature, respiration rate and pulse rate are measured and stored in an acquisition unit incorporating a circulating register for storing data covering many patients. An analog temperature signal is converted into binary coded decimal for visual presentation on a display of the acquisition unit. The display data is then stored in the acquisition unit memory by actuating a RECORD switch. An analog respiration rate signal and an analog pulse rate signal are also converted into binary coded decimal for sequential display and storage in the acquisition unit memory. Medical data from external sources may similarly be stored in the acquisition unit memory. This recording procedure is repeated for any number of patients desired up to the storage limit of the acquisition memory. Data stored in the acquisition unit is then transferred into a printer unit that accesses each memory location and prints the data on a separate label for each individual patient. The printer includes a hard wired minicomputer which reads in data from the acquisition unit and compares it with identifying codes for controlling a digital printer. Medical data for each patient stored in the acquisition unit is temporarily stored in a random access memory and sequentially compared with each of a plurality of identifying codes for control of the digital printer. After all patient data in the acquisition unit has been transferred into the printer memory, a signal is generated to enable clearing of the acquisition unit memory for subsequent use thereof.

This invention relates to an acquisition unit for acquiring datarelating to one or more physiological variables from a patient,displaying the data digitally and, upon operator approval, recording thedata in an internal memory. Further, the invention relates to a dataprinter responsive to data stored in an acquisition unit for a displaypresentation.

In the art of medical practice, it has been found desirable, undercertain conditions, to maintain a substantially running record ofcertain body functions, such as for example, body temperature, pulserate and respiration rate; these three comprising the basic bodyfunctions to be recorded. Heretofore, this vigilance has ordinarily beenmaintained by the nursing staff of the hospitals or other availableattendants, who periodically observe and manually record the conditionof the patient in accordance with a predetermined schedule. Thisobservation and manual recording is a time consuming technique whichlends itself to erroneous recording and analysis of a patient's bodyfunctions. Remedial measures taken after discovery of previouslyrecorded erroneous data during the next period of inspection are oftentoo late for the patient's condition.

The present invention provides for the automatic acquisition of datarelating to a patient's body functions and provides an instrument thatgenerates readily recordable signals accurately portraying temperature,respiration rate, pulse rate and additional data as desired. Animportant feature of the present invention resides in the use of a lightweight, portable, battery operated acquisition unit having an internalmemory for storing acquired data. The acquisition unit utilizes atemperature and respiration rate probe as described in the copendingpatent application of Emmett L. Hudspeht el al., filed Apr. 2, 1973,Ser. No. 346,952, assigned to the asignee of the present invention. Inaddition, the acquisition unit utilizes a standard pulse rate transducerfor acquiring data relating to this body function. Thus, the nursingstaff or other available attendant merely performs a mechanical task ofplacing the desired body function probe in or about a patient andoperates the acquisition unit for acquiring desired data.

In the field of medical care, accuracy of collected data relating to thebody functions of a patient is of significant importance. Erroneousdata, whether collected manually or automatically, presents thepossibility of an incorrect diagnosis of a patient's condition therebyleading to an erroneous prescription of remedial action. Another featureof the present invention allows the operator of the data acquisitionunit to override the automatically generated data with manuallygenerated data. In this situation, only the manually generated data istransferred to the acquisition unit memory and the automatic data isdiscarded. For future identification of the manually generated data, asopposed to the automatically generated data, the memory locationcontaining the manual data also contains a highlighting code. This code,when subsequently observed along with the accompanying data information,indicates that the operator exercised individual judgment in observing apatient's condition.

A problem often encountered when using portable battery poweredrecording equipment is that the failure of the power supply nullifies ordistorts previously recorded data. If this condition is observed, thefaulty or erroneous data may be disregarded thus avoiding seriousconsequences that could result from the reliance upon such data. Thatparticular series of data will, however, be lost and cannot berecovered. A more serious consequence is that the faulty or erroneousdata is not recognized as such and is relied upon in diagnosing apatient's condition. Still another feature of the present invention isthe use of an automatic data acquisition unit incorporating circuitryfor monitoring the condition of a battery supply and for restricting theunit's use when the supply drops below a first threshold. In this modeof operation of the acquisition unit, all data previously stored in theinternal memory is maintained for future recovery and utilization. Ifthe battery supply power decreases below a second threshold level, theinternal memory is deactivated and the stored data is lost, therebypreventing reliance on unreliable data.

Data acquired and stored in the internal memory of the acquisition unitof the present invention is transferred to a data printer that providesindividual patient printouts containing all the body function dataassociated with a particular patient. The data printer transfers all thebody function data for a particular patient into a random access memorywhere it is utilized, for comparison with character identification codesfor producing a printout label containing all the data for a particularpatient. Each printout label also includes a patient's identifyingnumber, the date the data was recorded and the time of recording. Theprinted data may then be assembled with a patient's record to provide acontinuous sequence of data relating to his condition. The data isuniformly presented for easy interpretation and analysis. Yet anotherfeature of the present invention is to provide a data printer responsiveto acquired data stored in an acquisition unit by a comparison of aplurality of character identifying codes with the acquired data.

In accordance with one embodiment of the invention, a medical dataacquisition and storage system comprises a display for providing avisual presentation of medical data inputed to the system. Automaticallyacquired data may be accepted through at least one information input andthis data is gated to the display for visual presentation thereof. Inaddition to accepting automatically acquired data, manually generateddata may be gated to the display for a visual presentation. When foundacceptable, data visually displayed is gated into storage means havingmultiple locations for storing in the data sequence. The sequence ofoperation is under the control of a state controller that establishesthe priority for gating data to the display means for any of the inputsources.

In another embodiment of the invention, a medical data acquisition anddisplay system comprises a data printer and one or more acquisitionunits for acquiring and storing a quantity of medical data from one ormore patients by at least one probe connected to the acquisition unit.The medical data in an acquisition unit is stored in a printer memory bytransfer means that gates the data from one of the acquisition units tothe memory. A display as part of the data printer includes multiplecharacters each identified by a particular identifying code; each ofthese identifying codes are compared with the stored medical data in theprinter memory and a display signal is generated upon a predeterminedcomparison condition. The display signal actuates the display to cause apreselected character to be presented. The entire system is controlledby a central controller for sequentially advancing each identifying codeand each entry of medical data for comparison.

Other features and advantages of the present invention will become morereadily apparent from the following description along with theaccompanying drawings and the appended claims.

Referring to the drawings:

FIG. 1 is a pictorial view of a battery powered data acquisition unitwith temperature, respiration rate and pulse rate transducers connectedthereto;

FIG. 2 is a pictorial view of a data printer responsive to acquired datain an acquisition unit for printing labels for individual patientssetting forth the acquired data along with a patient's identificationnumber, the date of entry and the time of entry;

FIG. 3 is a block diagram of the data acquisition unit includinganalog-to-digital converters for temperature, respiration rate and pulserate transducers;

FIGS. 4a, 4b, 4c, 4d and 4e comprise a schematic diagram for each of theblocks of FIG. 3 connected to the digital processor of FIG. 3;

FIGS. 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l and 5m comprise alogic diagram for the digital processor including various blocks withinthe dotted outline of FIG. 3;

FIG. 6 is a block diagram of the data printer of FIG. 2 for acceptingstored data from an acquisition unit to be printed on labels withpatient identification; and

FIGS. 7a, 7b and 7c comprise a flow chart of the operation of the dataprinter for comparing each entry in an acquisition unit with a characteridentifying code for a label printing operation.

Functionally, the system of the present invention can be divided intotwo component units or systems, the first is a data acquisition unit 10or TPR unit as shown in FIG. 1. Specialized transducer probes 12 and 14are utilized to measure a patient's vital signs such as temperature,pulse rate and respiration rate, and the acquisition unit converts thisdata into a digital format for storage in a circulating memory. Thesecond unit is a data printer 16, as illustrated in FIG. 2, andfunctions in response to information previously recorded in thecirculating memory of the acquisition unit 10 and producing hard copypatient labels 18.

Referring to FIG. 1, the data acquisition unit 10 includes a housing 20having a window display 22 and an array of sixteen keyboard switches 24.Typically, the display 22 provides a numerical readout 26 and otheroperating indicator lights as will be explained.

Coupled to the acquisition unit 10 is the temperature and respirationrate probe 12 generating an analog voltage varying with the patient'stemperature and a second analog voltage with a frequency equal to thepatient's respiration rate. The probe 12 may be of the type describedand claimed in the copending application of Emmett L. Hudspeth et al.,Ser. No. 346,952. Also coupled to the data acquisition unit 10 is thepulse rate probe 14 of the type commercially available to produce ananalog voltage with a frequency related to the patient's pulse rate. Inone form of a pulse probe 14, the probe comprises a clothespin-likeclamp that fits over a patient's finger and includes a light source andlight sensor. The light source illuminates the patient's fingertip andthe light sensor responds to the light transmitted through the fingertipwhich varies with a frequency related to the patient's pulse rate. Thevolume of blood in a patient's finger changes the absorption of lightfrom the source causing the light impinging on the sensor to change as afunction of the amount of blood in the patient's fingertip, which inturn varies with his pulse.

Considering the keyboard switches 24, there are four control switchesfor operator use. These are labeled RECORD, REPEAT, NOTE and MANUALSTART (all abbreviated in the FIGURE). The RECORD switch 28 is operatoractuated to transfer data being displayed in the numerical readout 26into the circulating memory of the acquisition unit and is active andeffective any time there is numerical information being presented in thereadout.

If the data visible in the display window 22 is unsatisfactory for anyreason, an operator actuates the REPEAT switch 30 to clear the displayfor accepting new data, either automatically acquired or manuallyentered from the keyboard switches. In the case of temperature, pulserate, or respiration rate, this causes a resampling of the analogvoltage produced by the probe, either probe 12 or probe 14. Thevariable, either temperature, pulse rate or respiration rate, isrecalculated and the newly calculated value presented at the numericalreadout 26. This new data can then be transferred into the internalmemory by actuating the RECORD switch 28 or the system can againcalculate a new data value by again actuating the REPEAT switch 30. TheREPEAT switch 30 is enabled any time the unit 10 is showing a number inthe numerical readout 26.

The NOTE switch 32 may be used whenever the unit is accepting dataeither from the probes 12 or 14 or other transducers. If data iscurrently being presented, but has yet to be recorded in the circulatingmemory, actuating the NOTE switch 32 causes the display to be cleared.Meanwhile, the unit is transferred to the note mode. At this point, theoperator may manually enter, by means of the numerical switches, codedmotes to provide additional information about the patient. For example,a pre-established code number represents weakened or irregular pulse.This code number may be recorded in the circulating memory by actuatingthe RECORD switch 28 after the operator has entered the code number whenin the note mode. In addition, this note mode can be used to recordrelatively unrelated data such as a patient's status, blood pressure,diet or medications. After recording a coded note, the acquisition unitreturns to its previous mode.

The acquisition unit 10 is normally activated automatically by the riseof the temperature at the probe 12 above 90°F. In special situationswhere the temperature portion of the probe 12 is not connected to theunit 10 or where the ambient temperature is always above 90°F., then theunit 10 can be activated by actuating the MANUAL START switch 38. Thisadvances the unit to the identification mode and permits normaloperation without requiring that temperature data be taken.

The acquisition unit 10 is provided with a four digit numerical readout26, which is capable of displaying numbers from 0-9999, and in additionthere are also five function indicators representing an identification(ID) mode, a temperature (T) mode, a pulse rate (P) mode, a respirationrate (R) mode, and an external (E) mode. When the unit 10 is functioningin each of the various modes, the appropriate function indicator will beilluminated with the NOTE mode indicated by the periodic flashing of anyfunction indicator.

The ID mode indicator is illuminated when the unit 10 is in theidentification mode and serves to inform an operator that the unit isready to accept numerical data pertaining to a particular patient'sidentification. When in the temperature mode, an indicator isilluminated to again identify to a user that the unit is ready to accepttemperature related data. Similarly, in the pulse mode the pulse modeindicator is illuminated and in the respiration mode the respirationmode indicator is illuminated to indicate that the unit is ready toaccept pulse and respiration related data, respectively. When the unitis accepting external data, other than from the probes 12 and 14, theexternal indicator is illuminated indicating that the unit is in a modefor accepting such externally generated data. Actuating the RECORDswitch 28 when data is present in the display always takes the unit 10out of a previous mode and causes the operation sequence to advance toanother sequencing mode.

Returning to the numerical keyboard, it comprises switches identified by0-9 for the manual entry of data for presentation at the readout 26including patient identification data. The numerical keyboard alsoallows the manual entry of data from patients who are too ill to acceptthe probes 12 and 14. In addition, the keyboard switches are also usedwhenever the numerical readout 26 is blanked and waiting for anidentification code to be entered. The numerical switches are alsoactively coupled to the system when there is data presented in thenumerical readout and actuating the numerical switches will modify thedisplayed data. To manually override data presented in the readout 26,the appropriate numbered switches are actuated and this data overridesthat in the display. When the first digit from the keyboard is entered,the complete data entry presented at the readout 26 is erased, and thecorresponding number is displayed in the least significant position ofthe display. Each time a succeeding numerical switch is actuated, thecorresponding number is displayed in the least significant position andall previously entered numbers are shifted one place to the left. Eachtime a number is entered, the number in the most significant position ofthe readout is lost. Data that has been manually entered via thekeyboard switches is specially coded internally and this special code isstored in the internal memory to later denote manual entries when thedata is printed.

In normal operation, the unit 10 will be utilized when making "rounds"in a hospital nursing unit. Here the nurse or health-care attendant willgo from bed to bed and acquire data relating to the temperature, pulserate and respiration rate from each patient in the unit. This data, onceacquired, is stored in the internal memory of the unit 10 for futurehard copy printout by the printer 16.

Referring to FIG. 2, after a nurse or health-care attendant has made around, or after the circulating memory of the acquisition unit 10 iscompletely loaded, the unit 10 is placed in one of two chutes 40 or 42of the printer 16. The printer is equipped to accept two acquisitionunits 10 at one time, although the printer will address the units one ata time to make a permanent recording of the data stored therein.Assuming that the unit 10 has been inserted into the chute 42, thecontents of the memory of the acquisition unit is printed on the labels18 by pushing a print button 44. A similar print button 46 is providedfor the chute 40 and is activated to address an acquisition unit in thechute 40 for printing out the data therein on the labels 18. Once theprint button for one position has been actuated, the data stored in therespective acquisition unit must be completely printed, or the unitremoved from the chute, before data stored in the second acquisitionunit in the opposite chute can be printed.

There are three additional controls on the printer, these are a PAUSEpush-button 48, a CONTINUE push-button 50 and a PAPER FEED push-button49. The PAUSE push-button 48 advances the printer operation to enter astop loop when it has completed printing the data for the present label.This control is provided to be utilized if the printer runs out oflabels 18, if the feed mechanism for the labels becomes jammed, or forany other reason requiring a temporary shut down of the printer.Printing may then be resumed by actuating the CONTINUE push-button 50whereby the printer sequence takes up printing with the data in theacquisition unit 10 which follows the data last printed. Alternatively,printing may be resumed by actuating a second time the print button, inwhich case the printer sequence resumes printing with the first datastored in the acquisition unit 10. The PAPER FEED push-button 49 isactuated to cause labels 18 to be advanced one line at a time for thepurpose of loading or alignment.

In addition to the push-button controls, the printer 16 is also providedwith date switches 52 for setting in a date to be printed on the labels18; there are also provided time switches 54 for setting in the time ofthe recording. This time data is also printed on the labels 18 andincludes the time of day and a notation of a.m. or p.m.

The printer mechanism itself (not shown) is a type referred to as aflying printer wherein a print drum rotates continuously. The printingmechanism is located below the transparent cover 56 in the print housing58. Printing is carried out by selecting a print hammer corresponding toa character disposed on the surface of the drum. In conventional largecapacity flying printers, the print hammers are generally electricallydriven but other driving techniques are possible.

The printer mechanism, per se, utilized in the present system is ofconventional design responding to signals generated within the printer16. The printer mechanism sends three signals to the control circuit ofthe unit 16, these are denoted as the printer reset signal, the TP andTL signals. A reset signal occurs once for each complete revolution ofthe print drum and the TP and TL signals occur for each row ofcharacters on the print drum. The TP signal occurs prior to the row ofcharacters passing under a print hammer and the TL signal occurs at thecompletion of a row of characters. Selection of a character to beprinted is accomplished by comparing a character identifying code withthe data transferred from the acquisition unit 10. This will beexplained in greater detail.

Referring to FIG. 3, there is shown a block diagram of the acquisitionunit 10 including a temperature analog circuit 60 and a respirationanalog circuit 62, both of which may contain part of the probe 12 and apulse analog circuit 64 which may contain the probe 14. Each of theanalog circuits 60, 62 and 64 connects to other circuitry within thehousing 20 wherein the analog signals are converted to binary codeddecimal (BCD).

Within the housing 20 of the acquisition unit 10, there is included astate controller 66 comprising logic for sequencing the unit throughvarious operational modes. Initially, the state controller 66 determineswhether the probe portions of analog circuits 60, 62 and 64 areconnected to the system. In addition, the state controller 66 respondsto a signal from the temperature analog circuit 60 to initiate operationof the acquisition unit.

As mentioned, the acquisition unit is enabled in an automatic mode whenthe temperature sensor in the probe 12 reaches 90°F. This temperaturesignal is coupled to the state controller 66 over a line 68 from theanalog circuit 60. After the circuit has been enabled in the automaticmode from the temperature analog circuit 60, the state controller 66generates a code to a data multiplexer 80 to initiate the illuminationof an ID mode indicator in the display 22. The system is now in the IDmode and an operator enters a patient's ID through the keyboard switches24. Actuating the switches 24 generates signals to a keyboard encoder 72that converts the closing of a switch into a binary code to a keyboardbuffer 74. Coded ID data in the buffer 74 is gated through a gate 76 toa display register 78 which is enabled by the display control 70 totransfer ID data through the data multiplexer 80 to the display 22. Theoperator upon verifying that the numerical readout 26 of the display 22accurately shows the patient's ID number, actuates the RECORD switch 28and data from the register 78 is transferred through a memory control 82to a memory 84.

The heart of the acquisition unit 10 is the solid state memory 84 inwhich the stored data is continually recirculated around a memory loopat an established rate. Typically, the memory 84 is composed of 12512-bit P-channel MOS dynamic shift registers circulated at 16 KHz bitrate. The circulating frequency to the memory 84 is generated in a clock86 that also provides clock pulses to a clock divider 88 to generateinternal clock pulses to various sections of the unit.

Thus, to initiate operation of the acquisition unit 10, the probe 12 isplaced in the patient's mouth, and the increase in temperature throughthe temperature level of 90°F causes the unit to turn on the ID modeindicator in the display 22 and initiate acquisition of data from thethree analog circuits 60, 62 and 64. The operator now enters thepatient's ID number by using the keyboard 24. When one of the numerickeys is actuated, the corresponding number is coded in BCD and stored inthe keyboard buffer 74; it is then shifted into the display register 78and displayed in the first numerical readout in the display 22. Up tothree additional ID digits may then be entered through the keyboard 24to the display register 78. After the correct ID number is presented inthe display 22, it is stored in the memory 84 by actuating the RECORDswitch 28. The acquisition unit 10 may be programmed to accept patientID numbers with more than four digits. This will be explained in greaterdetail.

When the RECORD switch 28 is actuated, the state controller 66automatically steps to the next function, which is the pulse mode. Thestate controller 66 again generates the proper binary code, which turnson the P mode indicator in the display 22. The pulse rate analog circuit64 generates an output signal having a repetition rate the same as thefrequency of the patient's pulse rate as sensed by the probe 14. Thispulse rate signal is connected to a pulse rate counter 90 that respondsto the signal generated by the pulse analog circuit 64.

Initially, the counter 90, which in effect is two registers in tandem,was reset by the state controller 66 in the idle mode. Thereafter, foreach pulse rate signal from the analog circuit 64, the first registeradvances one count and between the time when it has received four pulsesand the time when it has received twelve pulses it generates an enablesignal to the second register of the pulse rate counter 90. A window intime is generated which is proportional to the average period of thepatient's pulse and is in fact eight times the patient's average pulseperiod. During this length of time, between the fourth and twelfthpulses from the analog circuit 64, a clock from the divider 88 iscounted in the second register such that the count in this secondregister is inversely proportional to the pulse rate of a patient.

An output from the second register of the pulse rate counter 90 istransferred to a divider network 92 that consists of a digital dividerthat uses as a numerator one of two numbers hard wired into the circuit.The denominator for the divider network 92 is the count in the secondregister of the counter 90. The numerator hard wired into the divider isselected to scale the clock pulse count in the second register such thatafter completing the division process, the divider network 92 containsthe patient's average pulse rate in pulses per minute.

The divider network 92 is controlled by the output of a data transfercontroller 94 which in turn is sequenced from the display controller 70and the state controller 66. The pulse rate, in pulses per minute, inthe divider 92 is a binary code that is transferred through a gate 96 tothe display register 78 in response to a transfer signal from thecontroller 94. This transfer takes place after the divider network 92has completed the division process.

In one embodiment of the invention, the temperature, pulse rate andrespiration rate circuits all generate pure binary coded information.Prior to displaying such information in the display register 78, logiccircuitry, to be detailed, provides a serial binary to BCD (Binary CodedDecimal) conversion which results in the BCD data being stored in thedisplay register at the completion of the transfer of data thereto. Dataentered through the keyboard buffer or through external inputs, however,is supplied in BCD form and the display register 78 passively acceptsthis data with no conversion process.

The pulse rate code in the display register 78 is transferred throughthe data multiplexer 80 and displayed in the numerical readout 26 of thedisplay 22. If the operator is satisfied that the number in the display22 accurately reflects the patient's pulse rate condition, the RECORDswitch 28 is actuated and the data in the display register 78 istransferred through the memory controller 82 to the memory 84.

If the data presented in the display 22 does not satisfy the operatorthat it represents a true indication of the patient's pulse rate, thereare two alternatives available. One, the operator actuates the REPEATswitch 30 which sets the state controller 66 to reset both registers ofthe pulse rate counter 90 and the divider and serial transfer controller94 so that a new pulse rate measurement is made and transferred to thedisplay register 78. In the alternative, the operator may enter, throughthe numerical keyboard, a manual pulse rate measurement. This data isthen stored in the memory 84 by actuating the RECORD switch 28. Whenmanually generated data is stored in the memory 84, the memorycontroller 82 produces a binary code highlighting the memory entry tosignify that it was manually generated data.

Under normal operating conditions the state controller 66 advances theoperating sequence from an idle mode to an identification mode, from theidentification mode to the pulse rate mode, from the pulse mode to thetemperature mode and from the temperature mode to the respiration ratemode. When the operator actuates the RECORD switch 28 to transfer thedata in the display register 78 through the memory control 82 to thememory 84, the display control 70 generates a signal to the statecontroller 66 to advance the sequence to the next mode.

After recording the pulse rate data in the memory 84, the statecontroller 66 advances the system to the temperature mode. In thetemperature mode, a frequency signal from the temperature analog circuit60 is transferred to a temperature counter 98 in response to a controlsignal from the state controller 66. At the appropriate time in theacquisition cycle of the temperature mode, the cycles of the frequencysignal from the circuit 60 are counted for a fixed period of time in thetemperature counter 98 which has been preset with a count representing90°F. This results in a total in the counter 98 that is a function ofthe frequency of the circuit 60 and hence is a function of temperature.In effect, the counter 98 counts a variable incoming frequency for afixed period of time such that by presetting the counter to 90°F. andstarting the counter at a fixed time and stopping it at a fixed timelater there is generated a count that is a direct function oftemperature. Typically, the counter is enabled for 166 milliseconds andthis results in the counter being incremented one count for each 0.1°F.that the temperature probe is above 90°F.

In the temperature mode, the system has a capability of measuringtemperature by a direct count or by a predictive algorithm count.Normally, the predictive algorithm sequence is utilized as it produces atemperature reading in a shorter elapsed time period. In the directreading sequence, the total in the counter 98 represents the actualtemperature of the probe 12 at the time the temperature measurement ismade. Unless the probe 12 is left in the patient's mouth sufficientlylong to stabilize at the patient's temperature there results ameasurement which may differ from the patient's true temperature. Forthis reason, the direct count mode is normally used only when adequatetime has been allowed to permit thermal equilibrium between the probe 12and the patient's mouth.

In the predictive algorithm sequence, a measurement is achieved in thecounter 98 before the probe reaches equilibrium. When the temperature ofthe probe passes through 90°F., the counter 98 is enabled for apredetermined fixed length of time after a constant has been added togive a total reading representative of a patient's temperature beforethe probe is actually stabilized. Essentially, there is a prediction ofwhat the temperature will be when the probe has stabilized. Inimplementation of this addition of a constant, after the probe haspassed through 90°F., a fixed delay is initiated and the frequency fromthe circuit 60 is counted in the counter 98 for the fixed time periodafter this delay. In effect, the counter is started 1° higher than90°F., that is, 91°F., which accomplishes the addition of the constant.

As mentioned previously, an operator has the option of repeating ameasurement if that presented in the numerical readout 26 appears to bean erroneous measurement. When the operator actuates the REPEAT switch30, the temperature counter 98 bypasses the predictive algorithmsequence and uses the direct reading sequence. Also, when theacquisition routine is initiated by actuating the MANUAL START switch38, the temperature counter again bypasses the predictive algorithmsequence and uses the direct reading sequence for temperaturemeasurement. In the direct reading sequence, the frequency signalcoupled to the counter 98 is counted for a fixed period of time therebygiving a measure of a patient's temperature. Again, the counter startsat a base count of 90°F. and adds one count for each one tenth of adegree of temperature above this initiating level. The operator uses theREPEAT switch 30 to repeat the temperature measurement and may determinewhen thermal equilibrium of the probe 12 is achieved by comparingsuccessive measurements as shown in the numerical readout 26.

Summarizing the two temperature acquisition sequences, the predictivealgorithm sequence is started when the temperature of the probe 12 risesabove 90°F. After a predetermined delay time, the counter 98 is presetto a count of 91°F. and then actuated for a fixed period of time. Theresultant count in the counter 98 is 1°F. higher than the temperature ofthe probe 12 and represents a prediction of the temperature the probe 12would achieve if permitted to attain thermal equilibrium with thepatient's mouth. The direct reading sequence is started when theoperator presses the MANUAL START switch 38. It is also started any timea temperature measurement is repeated by actuating the REPEAT switch 30.Without delay the counter 98 is preset to a count of 90°F. and activatedfor a fixed time period. The count stored in the counter 98 reflects theactual temperature of the probe 12. The operator must determine whetherthe probe 12 has reached thermal equilibrium with the patient's mouth.

At an appropriate time after actuating the counter 98, the binary datastored therein is transferred through the gate 96 to the displayregister 78. During the transfer the data is converted to BCD by thedisplay register 78. Data in the display register 78, as explained, istransferred through the data multiplexer 80 to the display 22. If theoperator is satisfied with the data displayed, the RECORD switch 28 isactuated to transfer the temperature data from the display register 78through the memory control 82 to the memory 84. Again, a signal isgenerated to a state controller 66 to advance the sequence from thetemperature mode to the respiration rate mode.

Measurement of the respiration rate is similar to the pulse ratemeasurement. The respiration rate sensor, as part of the probe 12,consists of a bead thermistor placed in the nasal airstream of apatient. Respiratory air flow induces temperature changes in thethermistor which are amplified and conditioned in the respiration analogcircuit 62 to provide an analog frequency signal to a respiration ratecounter 100. Thereafter the operation in the respiration mode isanalogous to operation in the pulse mode.

The counter 100 registers pulses generated by the analog circuit 62 in afirst register which is used to generate a window for enabling a secondregister receiving a clock from the divider 88. At the second count inthe first register the second register is enabled and advances inaccordance with the frequency from the divider 88 until the sixth countin the first register. The count in the second register is proportionalto a period of the patient's respiration rate. Again, a scaling factoris present and the output of the respiration rate counter 100 istransferred to the divider 92 to produce a binary code equal to thepatient's respiration rate. In accordance with control pulses from thecontroller 94, the respiration rate binary code is gated through thegate 96 to the display register 78. During the transfer the data isconverted to BCD by the display register 78. Next, the data isdisplayed, and if found acceptable, transferred to the memory 84 byactuation of the RECORD switch 28.

At this time, under normal operating conditions of the acquisition unit10, a particular patient's medical data is stored in the memory 84. Thestate controller 66 returns the system to an idle mode. The operatorremoves the probes 12 and 14 from the patient. The unit is now ready forthe next patient.

In the previous description it was assumed that temperature, respirationrate and pulse rate data are taken from each patient. If any one of thethree probes for these measurements are not attached to the unit, thestate controller 66 skips over that measurement and advances thesequence to the next mode. Thus, the unit has the capability ofmeasuring temperature, pulse and respiration or any combination of thethree. Any one or more of these three can be measured and the othersautomatically deleted from the measurement process if the probes are notattached.

In addition to temperature, respiration rate and pulse ratemeasurements, additional medical data may be gathered for a patient andstored in the memory 84. This additional data is gathered from devicesidentified in FIG. 3 by the block 102. Examples of such external devicesinclude a blood pressure measuring transducer that will measure apatient's systolic and diastolic blood pressure and convert them intoBCD data, serialize the data and send it on an input line to the displayregister 78. Data is shifted into the display register 78 through thegate 96 under the control of the controller 94 and the external inputcircuit 104. In addition to numerical data, an identifying character isalso generated by the external device to identify the type of medicaldata. That is, data relating to a blood pressure measurement would beidentified with an appropriate coded prefix such that when printed outon the label 18 the measurement is readily identifiable. Thisidentifying character is also stored in the display register 78. Thedata is then presented in the display 22, and if found acceptable,shifted into the memory 84 by actuating the RECORD switch 28.

Another example of an external device is a transducer for measuring apatient's weight, such as in an out-patient clinic. Still anotherexample of an external device is a drop counter that measures thepatient's rate of intravenous infusion or urine output. Such a device issemi-permanently attached to the patient's bed and as the nurse orattendant measures the temperature, pulse and respiration of thepatient, this external device is coupled to the unit for storing in thememory 84.

In the sequence of operation of the acquisition unit 10, after the statecontroller 66 has stepped the sequence to the respiration rate mode andthe respiration rate data is transferred to the memory 84, the statecontroller checks to determine if any external devices are coupled tothe external input circuit 104. If an external device is detected, afirst pass at the external mode is made for transferring the BCD datagenerated by the external device to the memory 84. Note that theexternal device generates the BCD data and it is merely shifted throughthe system for display and storage in the memory 84.

As the operator actuates the RECORD switch 28 to transfer data from thefirst external device into the memory 84, the state controller 66 againcycles to the external mode to determine if a second such device iscoupled to the external input circuit 104. If a second device isdetected, the external mode is again repeated and the data stored in thememory 84. Again, the state controller 66 recycles to the external modeto evaluate if still a third device is coupled to the external inputcircuit 104. If a third device is detected, the sequence again cyclesthrough this mode to transfer data to the memory 84. If at any time thestate controller cycles to the external mode and an external device isnot coupled to the circuit 104, then the sequence advances to the idlemode as mentioned previously.

As mentioned, the sequence of operation of the acquisition unit 10 isfirst the ID mode, next is the pulse mode, then the temperature mode,and a respiration mode. Following, there is an external device modewherein data from externally connected devices is stored in the memory84. The memory is a serial memory, shift register, that is initiallyloaded with a start-of-data (SOD) word and an end-of-date (EOD) word.The SOD word is unique and used to indicate the first word of recordeddata in the memory 84. The EOD word is also unique and is used toindicate the last word of data in the memory at any particular time.

Whenever new data is transferred to the memory 84 it begins recording atthe position where the EOD word was previously located. After completingthe transfer of new data into the memory 84, the EOD word is againrecorded following the last data entry. For example, in the ID mode, theID data is stored in the memory 84 in the next position following theSOD word. After the ID data has been stored, the EOD word is written inthe next available location. Next is the pulse mode and as the pulsedata is transferred to the memory 84 it is first written over the EODword at the end of the ID data and the new EOD word is written after thepulse data. Thus, after each new data entry into the memory 84 the lastentry is a new EOD word.

Each item of patient data, whether it be ID number, temperature, pulserate, respiration rate, notes, or data from external devices, is storedin the memory prefixed by a coded mode word to unambiguously label thedata. These mode words identify the nature of each piece of data so thatthe printer 16 can sort and display them properly. Additionally, thefirst coded mode word associated with each patient's data is an ID modeword referred to as an IDA code. Like the EOD and SOD codes, the IDAcode is a unique code specifically reserved for the purpose offacilitating later separation of the data by the printer.

Referring to FIG. 4, and in particular to FIG. 4a, after the statecontroller 66 has received a signal indicating that the ID word has beenwritten into the memory 84, it advances to the pulse mode whereinsignals generated in the pulse analog circuit 64 are coupled to thepulse rate counter 90. The pulse rate probe includes a light source 106coupled to a switched power supply 108 to illuminate a patient's fingerto transmit light therethrough to a photocell 110. The volume of bloodin the patient's finger changes the absorption of light, in the spectralregion of sensitivity of the photocell 110, causing the resistance ofthe photocell to change as a function of the amount of blood in apatient's finger, which in turn changes with each heartbeat.

A logic signal for activating the switched power supply 108 is appliedover a line PL to a transistor 112 having a collector coupled to atransistor 114 through a base drive resistor 116. Also part of the drivecircuit for the transistor 114 is a diode 118 and resistors 120 and 122.A DC current in the collector of the transistor 114 is applied through aconnector 124 to the light source 106.

Both the light source 106 and the photocell 110 are coupled to groundthrough a connector 126. Also connected to the interconnection of thesource 106 and the photocell 110 is a probe present circuit comprising aresistor 128 connected to the positive terminal of a DC supply andthrough a connector 130 to the source 106 and photocell 110.Interconnecting the pulse probe 132 to the resistor 128 generates alogic signal at a terminal 134 that is transmitted over a line 136 tothe state controller 66 as a signal that the pulse mode should beentered.

A change in resistance of the photocell 110 is converted into a varyingvoltage as an input to an amplifier 138. The resistance to voltageconverter includes resistors 140 and 142 along with capacitors 144 and146. A feedback circuit for the amplifier 138 consists of resistors 148,150 and 152 along with capacitors 154 and 156. A voltage output from theamplifier 138 that varies with the resistance change of the photocell110 is applied for further amplification to the input of an amplifier158 through a coupling capacitor 160. Additional circuitry for theamplifier 158 includes resistors 162-165 and capacitors 166 and 168. Anoutput of the amplifier 158 is coupled through a capacitor 170 to aSchmitt trigger comprising transistors 172 and 174. The Schmitt triggeralso includes resistors 176-181.

Output pulses from the transistor 174 of the Schmitt trigger have arepetition rate that varies with the pulse rate as manifested by changesin resistance of the photocell 110. These voltage pulses are coupledthrough a capacitor 182 to a one-shot multivibrator comprisingtransistors 184 and 186. In addition to the transistors, the one-shotmultivibrator consists of resistors 188-193, a diode 194 and a capacitor196. Each pulse from the Schmitt trigger causes one output pulse to begenerated by the one-shot multivibrator. The function of the one-shotmultivibrator is to produce a series of uniform width voltage pulseshaving a repetition rate equal to a patient's pulse rate. These voltagepulses are transmitted over a line 198 to the pulse rate counter 90.

After writing the pulse rate data into the memory 84, the statecontroller 66 advances the acquisition unit 10 to the temperature modewherein temperature related voltage pulses from the temperature analogcircuit 60 are coupled to the temperature counter 98. As part of thetemperature analog circuit 60 there is a temperature probe 200comprising a thermistor 202 coupled to ground through a connector 204.Also connected to the thermistor 202 through a connector 206 is acircuit for sensing the presence of the probe 200. This circuit includesa resistor 210 connected to the positive terminal of a DC supply andgenerating a voltage at the terminal 212 when the probe is connected tothe analog circuit 60. This voltage at the terminal 212 is a logicsignal applied to the state controller 66 over a line 214. Whenever avoltage on the line 214 is present, the state controller 66 advancesfrom the pulse rate mode to the temperature mode. Otherwise, thetemperature mode is skipped and the state controller advances to thenext mode.

Basically, the analog circuit 60 is a bridge amplifier where thethermistor 202 is part of a resistance bridge including resistors 216,218 and 226, along with a variable resistor 220. An unbalance of thebridge caused by a variation in temperature at the thermistor 202produces a voltage differential at the inputs of an amplifier 224. Thisunbalance voltage to the amplifier 224 is the difference between thetemperature at the thermistor 202 and a bridge balance temperature asset by the variable resistor 220.

Also forming a part of the circuitry for the amplifier 224 is resistor228 along with capacitor 230 and a gain potentiometer 234.

An output voltage from the amplifier 224 is applied to the input of alevel sensor amplifier 236 through an input resistor 238. A second inputto the amplifier 236 is generated at the wiper arm of a potentiometer240 and coupled to the amplifier through a resistor 242.

The potentiometer 240 is set at the desired turn-on temperature of 90°F.and whenever the output of the amplifier 224 exceeds the voltage at thewiper arm of the potentiometer 240 the amplifier 236 generates a voltageoutput of a line 68 to the state controller 66. It is the voltage signalon the line 68 that turns on the acquisition unit to cause the statecontroller 66 to advance from the idle mode to the ID mode.

Also coupled to the output of the amplifier 224 is an amplifier 246 aspart of a unijunction transistor oscillator to convert the voltageoutput of the amplifier 224 into a frequency signal. The amplifier 246is differentially connected with one input coupled to ground through aresistor 248 and the second input connected to the amplifier 224 througha resistor 250. The output voltage from the amplifier 246 is coupledthrough a biased diode 252 to a unijunction transistor 254 having baseone and two terminals connected through resistors 256 and 258 to DCsupplies. The unijunction transistor oscillator is of a conventionaldesign and includes a bias resistor 260 coupled to a DC supply and alsoto the timing capacitor 264. Amplifier 246 linearizes the charging oftiming capacitor 264 and controls the charging current of the timingcapacitor 264 in response to changes in the voltage output of amplifier224. Additional components for the oscillator are output transistor 262and its bias supply resistor 266. A frequency varying with thetemperature at the thermistor 202 is generated at the collector of thetransistor 262 in response to the oscillator signal applied at itsemitter and is applied over a line 268 to the temperature counter 98.

As explained, after the temperature data has been stored in the memory84, the state controller 66 advances the acquisition unit 10 to therespiration mode wherein signals generated at the respiration analogcircuit 62 are coupled to the respiration rate counter 100. The analogcircuit 62 includes a thermistor 270, as part of the temperature probe200, that senses the rise and fall in the temperature of air passingover it. The patient exhales warm air which flows past the thermistor270 and inhales cool air which is pulled back across the thermistor.This causes a cycling variation in the resistance of the thermistor 270.

This variation in resistance of the thermistor 270 is converted into avarying voltage by a circuit including resistors 272 and 274 along withcapacitors 276 and 278. The voltage is then applied to an amplifier 280having a feedback network including components similar in connection tothose for the amplifier 138 of the pulse analog circuit 64.

Basically, the respiration analog circuit 62 is similar to the pulseanalog circuit 64. As such, it is provided with a probe sensing resistor282 connected to the thermistor 270 through a connector 284 and thencecoupled to ground through connector 204. A voltage generated at theterminal 286 indicates that the probe is coupled to the system and avoltage on the line 288 is applied to the state controller 66 as aninstruction for the controller to sequence to the respiration rate mode.

An output of the amplifier 280 is coupled through a capacitor 290 to oneinput of a differential amplifier 292 having associated circuitryincluding resistors 294-297 and capacitors 298 and 300. From theamplifier 292, a voltage varying with the resistance of the thermistor270 is coupled to a Schmitt trigger comprising transistors 302 and 304and circuitry therefor. The output of the amplifier 292 is coupled tothe transistor 302 through a capacitor 306. Also associated with thetransistors 302 and 304 are resistors 308-313.

The Schmitt trigger functions as a pulse forming circuit responsive tothe output of the amplifier 292. Pulses from the Schmitt triggergenerated at the collector of the transistor 304 are coupled through acapacitor 314 to a one-shot multivibrator consisting of transistors 316and 318. Bias voltages for the transistors 316 and 318 are set byvarious resistor networks including resistors 320-325. Also associatedwith the one-shot multivibrator is a diode 326 and a capacitor 328.Uniform width voltage pulses are generated on a line 330 having arepetition rate equal to the respiration rate and coupled to therespiration rate counter 100 for storage in the memory 84.

Referring to FIG. 4b, data generated by the circuits 60, 62 and 64 isgated through the gate 96 into the display register 78 and through adata multiplexer 80 to the display 22 over lines Da-Dg. In addition,control signals are coupled through the register 78 on lines 328 and329. Control signals on the lines 328 and 329 are decoded in logicincluding NAND gates 332-335 and inverting amplifiers 336 and 338.

Decoded control signals from the NAND gates 332-335 are applied to aswitching network consisting of transistors 340-347. Specifically, NANDgate 332 drives the switching transistor 341 through a resistor 348, theNAND gate 333 drives the switching transistor 343 through a resistor350, the NAND gate 334 drives the switching transistor 345 through aresistor 352 and the NAND gate 335 drives the switching transistor 347through a resistor 354.

Each of the switching transistor pairs drives one array of lightemitting diodes (LEDs) as part of the display 22. Transistors 340 and341 drive a diode array 356, the transistor pair 342 and 343 drives adiode array 358, the transistor pair 344 and 345 drives a diode array360 and the transistor pair 346 and 347 drives a diode array 362. Theindividual diodes of each array are interconnected and coupled tocontrol transistors 364-370 which in turn are individually connected toone of the data lines Da-Dg.

Operationally, control signals on the lines 328 and 329 along with datasignals on the lines Da-Dg set the various transistor switches toilluminate the LED arrays 356, 358, 360 and 362 to present a numericaldisplay in the display 22.

In addition to displaying data, there is also presented in the display22 mode indicators comprising LEDs 372-379. The LED 372 is an indicatorfor the pulse rate signals generated on the line 198 of the circuit 64.This diode is controlled by switching transistors 380 and 382interconnected through a resistor 384 to the line 198. The LED 373 is anindicator for respiration rate signals as generated on the line 330 ofthe circuit 62 and is controlled by switching transistors 386 and 388interconnected through a resistor 390 to the line 330. The array of LEDs374-379 are mode indicators and each is respectively controlled by aswitching transistor 392-397. Each of the switching transistors isconnected to the output of decoders 398 and 400 interconnected tocontrol line ML1, ML2, ML4 and ML8.

The operating mode of the acquisition unit is controlled by the statecontroller 66 and indicated by illuminating one of the LEDs 374-379.These diodes are controlled by coded data generated in the datamultiplexer 80. This coded data is coupled to the decoders 398 and 400where it is decoded to energize the correct LED.

In addition to controlling the LEDs 374-379, the output of the decoders398 and 400 is also coupled to transistors 402-405 and inverter 399 aspart of a selection network for external devices 102 coupled to theacquisition unit. These control signals to the external devices 102 aregenerated on the lines 406-409 and 414.

Also supplied to the display 22 are clock pulses on lines 410 and 412.The clock pulses are utilized to strobe the light emitting diodes suchthat they are energized for only a brief period. Typically, the clockpulses strobe the light emitting diodes such that they have about a 5%duty cycle during which time they are illuminated very brightly and theeffect is that they appear to be of average brightness continuously.

Referring to FIG. 4c, data in the register 78, as presented in thedisplay 22, is transferred to the memory 84 in response to a commandfrom the keyboard 24. The keyboard 24 comprises an array of momentarycontact switches 416-429 each having a common connection to ground.Actuating any one of the keyboard switches provides a voltage to eitherencoder 430 or encoder 432. The encoders 430 and 432 are part of thekeyboard encoder 72 and function to convert the voltage signal generatedby actuating one of the key switches into a binary code on the outputlines 434-438. Also forming part of the encoder 72 and associated withthe line 434 is logic including NAND gates 440-443, and NOR gate 444 andinverting amplifiers 446 and 448. An output code on the lines 434-438 iscoupled to the keyboard buffer 74.

Also illustrated in FIG. 4c is a set-up circuit 450 for initiating theoperation of the acquisition unit 10. The set-up circuit consists of aone-shot multivibrator 452 set by the output of an AND gate 454 coupledto a NAND gate 456. An output from the one-shot multivibrator 452 iscoupled through an ID length state control 458 comprising switches 460and 462.

Referring to FIG. 4d, the memory 84 comprises an array of circulatingregisters responsive to clock pulses for continuously circulating datastored therein. Data to be stored in the memory 84 from the memorycontrol 82 is transferred over data lines 464 otherwise identified asSBl, SB2, SB4 and SB8. These data lines individually connected to ANDgates in an array 466 also including gates individually tied to theoutput of one of four flip-flops in an array 468. Pairs of AND gates inthe array 466 are coupled to individual OR gates in an array 470 whichin turn are connected in pairs to either dual shift register 472 or 474.The dual shift registers 472 and 474 are part of the main memory thatalso includes dual shift registers 476, 478, 480 and 482. Output linesfrom the dual shift registers 480 and 482 are coupled to logic forproviding the EOD signal and SOD signal and also to logic fortransferring the memory data to the system printer, as will beexplained. In addition, the output lines of the dual shift registers 480and 482 are coupled to the input of the flip-flops in the array 468 andit is this interconnection that produces recirculation of data throughthe memory. This recirculation is controlled at a clock rate generatedon a line 484 as an output from the clock 86.

The logic for producing the EOD signal and SOD signal comprises NANDgates 486-488 and inverting amplifiers 490-493. Logic for coupling theoutput of the registers to the printer includes inverting amplifiers494-496 and 498-502. The output data from the memory is coupled to theprinter through terminal hardware 504.

Data is written into the memory 84 in response to a "write" signalgenerated as a result of actuating the RECORD switch 28 to generate asignal to a NAND gate 506. An output from the NAND gate 506, or the"write" signal from the memory control 82, is connected to one input ofeach of the AND gates in the array 466.

Clock signals for operating the entire acquisition unit 10 are generatedby a clock 86 including a crystal 508. The crystal frequency steps afrequency divider 510 coupled to logic including NAND gates 511 and 512along with inverting amplifiers 514-521. The output of the invertingamplifier 520 is the primary clock frequency for the system generated onthe line 484, and the output of the inverting amplifier 521 is the logicinverse of the primary clock signal and is generated on a line 522.

Also forming part of the clock 86 are transistor switches 524-527 withthe transistors 524 and 525 connected to inverting clock driveramplifier 529 and the transistors 526 and 527 connected to invertingclock driver amplifier 528. The outputs of the clock drivers 528-529provide two phase nonoverlapping clock signals to dual shift registersof the memory 84. The output of the clock drivers 528-529 are alsocoupled through a NAND gate 530 and an inverting amplifier 532 to theterminal hardware 504 for supplying a synchronizing clock to theprinter.

Referring to FIG. 4e, there is shown the external device block 102 withdetails of an illustrative external device 534. The external device 534includes logic for responding to an inquiry from the state controller 66and for producing the BCD data signals to the display register 78. Inputsignals REX, PWR, θ5 are provided to the external device 534 if presentand also to external devices 566 and 568 if present. Input signal SEX1is also provided to the external device 534 while external devices 566and 568 receive input signals SEX2 and SEX3 respectively. All threeexternal devices 534, 566 and 568 share a common output line ESI 564. Inthe idle state of the acquisition unit 10 the signal PWR is set to alogic level which causes all connected external devices to relinquishcontrol of the common status and data line ESI 564. During its sequenceof operation the state controller 66 generates control signals which aredecoded by the decoder 398 and applied to the transistor 403 to generatea "select external device 1" (SEX1) signal on the line 407. If externaldevice 534 is connected to the acquisition unit 10, it assumes controlof the ESI line forcing it from a first logic level to a second logiclevel. This transition of the ESI line 564 from the first logic level tothe second logic level is sensed by NAND gates 742 and 743 of theexternal input 104 as shown in FIG. 5l. Upon sensing the propertransition of the ESI line 564 the gates 742 and 743 generate an ECsignal to the state controller 66 indicating that the first externaldevice is connected. The external device maintains the ESI line 564 atthe second logic level until it completes its measurement and isprepared to send its processed data to the acquisition unit. In theillustrative circuit this delay is simulated by the one-shotmultivibrator 544. When the selected external device is ready totransmit its data it returns the ESI line 564 to the first logic level.When the state controller 66 advances its sequence to the point foraccepting data from external devices and the selected external devicehas indicated that its measurement is complete, the NAND gate 747 of theexternal input 104 of FIG. 5l generates a logic signal ERDY to theserial data transfer controller 94 of FIG. 5j. Upon receipt of the ERDYsignal the data transfer controller generates a sequence of pulses θ5 onthe line 555 to the external device 102. The sequence of pulses on theθ5 line are used as clock pulses by the external device to synchronizethe transfer of its BCD data which it sends to the data acquisitiondevice 10 on the ESI line 564. In addition to its collected data, theexternal device sends to the acquisition unit an identifying code forsubsequent use by the printer 16 in properly identifying the origin ofthe data. The transmitted data is displayed in the display 22. At theoperator's discretion the data measurement by the external device may bereinitiated by pressing the REPEAT switch 30 of the keyboard 24. Thisaction causes a pulse on the REX line to the external devices and theexternal device which has been previously selected collects andtransmits new data. Use of the RECORD switch 25 will transfer the datareceived from the external device to the memory 84. When the data fromthe first external device 534 is recorded a pulse generated on the PWRline will cause the first external device 534 to relinquish control ofthe ESI line.

In a similar manner additional external devices are interrogated and ifattached will sequentially assume control of ESI line 564 indicatingtheir presence. Up to three external devices may be attached to theacquisition unit 10.

The structure of an illustrative external device is shown as block 534of FIG. 4e. Logic including NAND gates 536-539, an AND gate 540 and aninverting amplifier 542 receives the commands from the state controller66 to set a one-shot multivibrator 544. A ready signal is generated atthe output of the one-shot multivibrator 544 through a NAND gate 546 anda count enable signal is generated at the output of one-shotmultivibrator 548 having an input interconnected to an AND gate 550 anda NAND gate 552, the latter receiving through line 555 a clock from thedivider and serial data transfer controller 94. Also receiving a clockis a flip-flop 554 through a NAND gate 556. The flip-flops 554 and 558constitute a binary counter having outputs coupled through a NAND gate560 to a NAND gate 562 in turn tied to the NAND gate 546 to generate anexternal signal input to the input logic 104 on a line 564. This signalis initiated by the control signals on lines 406, 407 and 414 and issynchronized with the clock signal on line 555. External devices 566 and568, shown only in block form, may be similar to the external device534.

Temperature, respiration rate and pulse rate data along with informationgenerated by external devices are processed through the acquisition unit10 to the display 22 and subsequently stored in the memory 84. Theentire sequence of operation of the acquisition unit 10 is under thecontrol of the state controller 66 and various logic networksinterconnected thereto. The state controller essentially controlseverything in the acquisition unit through the various modes includingthe identification mode, pulse rate acquisition mode, respiration rateacquisition mode, the temperature acquisition mode and a mode forreceiving information from external devices.

Referring to FIGS. 5a-k, there is shown logic circuitry for the statecontroller 66 and interconnected logic networks within the dottedoutline 560 of FIG. 3. Although a logic element by element descriptionof FIG. 5 will not be given herein, a basic discussion of the diagramwill be presented to enable a better understanding of the acquisitionunit 10. Standard logic symbols and interconnecting line format areutilized in the logic circuitry of FIG. 5.

Referring to FIG. 5a, there is shown a logic diagram for the statecontroller 66 wherein the five flip-flops 562 generate the control bitsfor sequentially operating the acquisition unit 10 through the variousmodes. These control bits are decoded in NAND gate logic 564interconnected to inverter amplifiers 566 to generate all the modecontrol signals for the acquisition unit. Primary clock pulses for thestate controller are applied thereto over a line 568.

An end-of-data signal from the memory 84 is applied to NAND gate 572 anda start-of-data signal is applied to a NAND gate 574 as part of the NANDlogic associated with the flip-flops 570 and NAND gates 596 fordetecting the full memory condition.

A feature of the acquisition unit 10 is that it will accept varyinglength identification codes from a four digit code up to a 12 digitcode. Control signals on the lines 576 and 578 are generated to thestate controller 66 to identify the length of the ID code. When a fourdigit ID code is utilized, signals on both the lines 576 and 578 are ata logic level to set the flip-flops 562 for a shortened ID modeoperation. For the eight digit ID code, a logic signal is generated onthe line 576 as a control bit to the flip-flops 562. For a 12 digit IDcode, a signal is generated on the line 578 to set the flip-flops 562 toenable a longer time in the ID mode. The logic signals on lines 576 and578 are programmed by setting ID length state switches 460 and 462 ofFIG. 4c. The state controller 66 in turn generates control bits on lines580 and 582 to the memory control 82 to set the logic of the memorycontrol to record the proper ID code length identifiers in the memory84.

Also establishing control of the flip-flop 562 is the output of a NANDgate 584 receiving the TC, RC and PC probe connection indications fromthe temperature probe, respiration rate probe and pulse rate probe,respectively, and the EC external device connection indication from theexternal input circuit 104. It is the NAND gate 584 and additional logicconnected to the TC, RC, PC and EC signals that determines whether theacquisition unit will proceed in the temperature, respiration rate,pulse rate, or external modes. The TC signal, RC signal and PC signalare received directly from the temperature circuit 60, the respirationrate circuit 62 or the pulse rate circuit 64, respectively. The ECsignal is extracted from the external device signal line 564 by theexternal input circuit 104.

As discussed previously, the acquisition unit becomes operational whenthe temperature sensor passes a predetermined temperature level. Thestate controller 66 receives the temperature actuating signal at a NANDgate 586 and inverts this signal through an inverting amplifier 588 forconnection to the temperature counter 98 of FIG. 5k. A start signal isalso applied to the temperature counter 98 from a flip-flop 590 as partof logic circuitry including NAND gates 726 coupled to receive controlpulses from the state controller 66.

NAND gate logic 592, as part of the state controller, provides variouscontrol signals to the pulse counter 90 and the respiration rate counter100, both illustrated in FIG. 5h, and the temperature counter 98 toreset all the counters between patients and to reset the appropriate onewhen the REPEAT switch 30 is actuated. When operating in the externalmode, a flip-flop 594 receives an ESI signal from the external device.The flip-flop 594 causes the state controller 66 to return to its idlestate if the operator attempts to repeat a data measurement from anexternal device which has been disconnected from the acquisition unit10. Also generated by the state controller 66 is a memory full signal ata NAND gate 596 coupled to the data multiplexer 80 of FIG. 5e forgenerating an indication in display 22 when memory 84 is filled tocapacity.

Referring to FIG. 5b, there is shown internal logic for the keyboardbuffer 74 receiving encoded data signals, K8, K4, K2, K1 and PK16 fromthe keyboard encoder 72. Included in the logic for the keyboard bufferare NAND gates 598 for providing binary encoded data on lines KL1, KL2,KL4 and KL8 to the display register 78 of FIG. 5d through the gate 76.Also included within the keyboard buffer 74 for internal sequencingcontrol are flip-flops 600 and 602 and associated NAND gate logic.Various control signals are transferred between the keyboard buffer 74and the state controller 66. These include a SPB signal, an REC signal,an I signal and an SU signal coupled to the flip-flops 600 and 602.Control signals generated by the keyboard buffer 74 are provided at theoutputs of NAND gates 604.

Another control section of the logic of FIG. 5 is the display control 70wherein signals S2', SO, RPT*, REC, I, S2' and Δ are transferred betweenthe state controller and the display control.

Referring to FIG. 5c, there is shown logic circuitry for the displaycontrol 70 including four flip-flops 606 and associated NAND gate logicfor generating the A, A, B, B, C, D, D and DD signals coupled to thedata multiplexer 80 of FIG. 5e and the memory control 82 of FIG. 5f.Logic circuitry for driving the flip-flops 606 includes NAND gates 608responsive to the REC signal and the REC signal from the keyboard buffer74. These are the record signals for transferring data in the displayregister 78 through the memory control 82 to the memory 84. Timingsignals to the display logic are applied thereto through NAND gatearrays 610 and 612. Also included as part of the display control 70 islogic 614 coupled to the display register 78 of FIG. 5d. NAND gate logic616 is coupled to the flip-flops 606 and provides the S1, S0 and S0signals with the S1 signal coupled to the data multiplexer 80 and thememory control 82, the S0 signal connected to the memory control 82 andthe data transfer controller 94 of FIG. 5j and the state controller 66,and the S0 signal to the state controller 66. Also generated by thedisplay control 70 is an EM signal to the memory control 82.

Referring to FIG. 5d, there is shown logic circuitry for the displayregister 78 controlled by signals generated at the logic 614 of FIG. 5c.The display register 78 includes NAND gate logic 620 coupled to thekeyboard buffer 74 of FIG. 5b, and in particular to the NAND gates 598.Connected to the outputs of the NAND gates 620 is an array of flip-flops622 interconnected to NAND gate logic 624. The outputs of the NAND gates624 are coupled through four flip-flops 626 to NAND gate logic 628. Inturn, the outputs of the NAND gate logic 628 are coupled through fourflip-flops 630 to NAND gate logic 632. From the NAND gate logic 632, thesignals are applied to four flip-flops 634 having outputs A4, B4, C4 andD4 connected to the data multiplexer 80 of FIG. 5e.

Also included as part of the display register 78 is NAND gate logic 636coupled to the memory control 82. As connected, the display register 78comprises a recirculating register and includes NAND gate logic 638 forcontrolling the binary to BCD conversion process. Also applied to thedisplay register 78 at the NAND gate logic 632 are signals ISI, ESI andDTIN.

Referring to FIG. 5e, data signals generated by the display register 78are coupled to the data multiplexer 80 at NAND gate logic 640 havingoutputs coupled to decoding logic 642. The decoding logic converts theoutput of the display register 78 into a signal format for driving thedisplay 22. Also forming part of the data multiplexer 80 is NAND gatelogic 646 responsive to control signals for generating the variousindicator messages at the display 22, as explained previously. NAND gatelogic 644 is responsive to the system clock pulses, the displayed data,and display control 70 to prevent the display of nonsignificant leadingzeros in the display register 78.

Referring to FIG. 5f, there is shown logic circuitry for processing datafrom the display register 78 for transfer to the memory 84. Input datato the memory control 82 is coupled to NAND gate logic 648 that in turndrives a NAND gate array 650 generating SB1, SB2, SB4, SB8 and WRITEsignals to the memory 84. In addition to receiving data from the displayregister 78, the memory control 82 connects to the state controller 66and the display control 70. Thus, the memory control 82 provides controllogic for addressing the memory 84. Forming part of the logic for thememory control 82 is a NAND gate array 652 responsive to signals fromthe display control 70.

The entire acquisition unit 10 is sequenced in accordance with clockpulses generated at the clock 86 and divided by the clock divider 88.Referring to FIG. 5g, there is shown logic circuitry for the clockdivider 88 including a flip-flop array 654 each having outputsselectively coupled to a NAND gate 656 or a NAND gate 658. NAND gate 657provides a 20 Hz clock signal for system timing requirements.

Also forming part of the clock divider is a NAND gate 660 generating theprimary clock frequency of 16 kilocycles for the acquisition unit and atthe output of a NAND gate 662 there is generated a 16 kilocycle clock180 electrical degrees displaced from the output of the gate 660. Theoutput from the NAND gate 660 is coupled to flip-flops and NAND gatelogic 664 to generate a 2 kilocycle clock at the output of a NAND gate666. Also provided by the clock divider 88 is a 5 Hz timing signal atthe output of a flip-flop 668. The primary 16 KHz clock is coupled tothe logic circuitry of FIGS. 5b, c, d, e, j and k and the 5Hz timingsignal from the flip-flop 668 is applied to the logic of FIGS. 5h and5m. The 20Hz timing signal from NAND gate 657 is coupled to the logic ofFIG. 5h. The 2KHz clock signal is coupled to the temperature counter ofFIG. 5k and the 16KC signal is applied to the data multiplexer 80 ofFIG. 5e.

After completion of the ID mode, the acquisition unit advances to thepulse mode wherein pulses generated at the output of the pulse circuit64 are applied to the pulse counter 90. Referring to FIG. 5h, there isshown a logic diagram of the pulse counter 90 including a registercomposed of nine flip-flops 670 each having an individual output tied toone input of a NAND gate in an array 672. The flip-flops 670 are steppedby the output of a NAND gate 674 as part of logic including fourflip-flops 676 and associated NAND gates.

Pulse signals generated by the analog circuit 64 are coupled to thefirst flip-flop of the array 676 to advance the counter in accordancewith a patient's pulse rate. Operation of the counter is controlled by aPC signal applied to NAND gate 678 and a PRPT signal connected toflip-flop arrays 670 and 676. In the pulse rate mode, the signal S4' isapplied to the NAND gate 672 to transfer the total count to the pulseand respiration rate divider 92 of FIG. 5i. The pulse rate data isgenerated by the counter 90 at the output of the NAND gates 680-684 and694-697.

Following the pulse mode, the acquisition unit advances to thetemperature mode and then to the respiration rate mode and a logicdiagram of the respiration rate counter 100 is also detailed in FIG. 5h.Both the counters 90 and 100 are similar with the respiration ratecounter including an array of flip-flops 686 having individual outputsconnected to one input of a NAND gate in an array 688. The respirationrate pulses from the analog circuit 62 are applied to the firstflip-flop in an array 690 having associated NAND gate logic including aNAND gate 692 responsive to the probe connection signal from the circuit62.

In the respiration rate mode a S6' signal is applied to the NAND gates688 to transfer the count in the flip-flops 686 to the divider 92. Thetotal count from the counter 100 is generated at the output of NANDgates 694-697 and 680-684.

At the end of the time interval during both the pulse rate mode and therespiration rate mode, the total count from the counter 90 or thecounter 100 is transferred to the pulse rate and respiration ratedivider 92 as shown in FIG. 5i. FIG. 5i is a logic diagram of thedivider 92 and includes a register of flip-flops and interconnected NANDgates in an array 700. The total count data from either the counter 90or 100 is applied to the array 700 through an EXCLUSIVE OR gate array702, NAND gate logic 704 and NAND gate logic 706. Also coupled to theoutput lines of the counters 90 and 100 and the EXCLUSIVE OR gate array702 is NAND gate logic in seven arrays 708.

Operationally, the NAND gate arrays 708 and the EXCLUSIVE OR gate arrays702 along with the NAND gate logic 704 and 706 combine with the array700 to complete the division function as described earlier to providebinary data to the display register 78 for a visual presentation in thedisplay 22. This transfer of data is controlled by the data transfercontroller 94 by signals coupled to logic including NAND gates 710 andflip-flops 712 and 714.

Primarily, the divider 92 is sequenced by the controller 94 in thevarious modes as established by the state controller 66. Referring toFIG. 5j, there is shown a logic diagram for the data transfer controller94 generating control signals at the output of NAND gates in an array716. The NAND gates in the array 716 have inputs coupled to terminals ofan array of five flip-flops 718 and NAND gate logic 720.

Input control signals from the state controller 66 are received at theflip-flop array 718 which also generates N, N, M, P, R, b, and DSIsignals to the temperature counter 98 of FIG. 5k. The flip-flop array718 is also coupled to the NAND gate logic 720 which receives theprimary clock signal and a pulse rate and respiration rate ready inputat a NAND gate 722.

In the normal sequence of operation of the acquisition unit 10, the unitenters the temperature mode following the pulse mode. Frequency signalsproduced by the temperature circuit 60 are applied to the temperaturecounter 98 that is actuated for a predetermined time interval. This timeinterval is generated by flip-flop array 734.

Referring to FIG. 5k, there is shown a logic diagram of the temperaturecounter 98 receiving temperature related frequency signals on a line 724coupled to selected NAND gates in an array 726. Also coupled to the NANDgates of the array 726 are control signals from three flip-flops 728having inputs connected to a NAND gate array 730. Connected to the NANDgate array 730 is the TRPT signal and the TRPT signal from the statecontroller 66. These signals as applied to the flip-flops 728 arecoupled to the NAND gate array 726 for stepping a counting registercomprising flip-flop arrays 732, 734 and 736. A totalized count asgenerated in the flip-flop arrays 732 and 736 is applied to a NAND gatearray 738 that receives control signals from the data transfercontroller 94.

Also applied to the temperature counter 98 is the temperature activatingsignal (TL_(*)) applied to selected gates of the array 726. This arrayof NAND gates 726 also receives a START signal and generates atemperature ready TRDY signal and a TRDY signal to the controller 94 andthe display register 78, respectively. Both the 16 kilocycle clock andthe 2 kilocycle clock are coupled to the temperature counter 98 forsequencing thereof.

During the external mode operation of the acquisition unit 10,externally generated data from devices 102 are transferred through theexternal input 104 to the gate 96. Referring to FIG. 5l, there is shownlogic for the external input circuit 104 including NAND gates 740-747.The NAND gates 740, 744, 745 and 746 are coupled to the input controlsignals and the NAND gates 743, 744 and 747 generate output signals toother sections of the logic of FIG. 5. Basically, the external inputcircuit 104 is logic for determining the status of the external device102.

Although not specifically shown in FIG. 3, the line encoder of FIG. 5mis associated with the data multiplexer 80 for converting the timing andcontrol signals from the state controller 66 into control signals to thedisplay 22 and to the external devices 102 and to the switched powersupply 108. Input signals are connected to the line encoder at NANDgates 748-756 and these gates in turn are coupled to inputs of a NANDgate array 758 for decoding into ML1, ML2, ML4 and ML8 signals to thedisplay 22 and external devices 102 as shown in FIG. 4b and PL to theswitched power supply 108 of FIG. 4a. The output signals from the lineencoder are generated at the terminals of NAND gates 760-763 and 758.

Referring to FIG. 6, after an attendant has made a round and stored inthe memory 84 the pulse rate, temperature and respiration rate ofpatients under his control, or after the memory 84 is completely loaded,the acquisition unit is placed in one of the two chutes 40 or 42 of theprinter 16 illustrated by a block diagram wherein the print buttons 44and 46 are part of block 101 connected to random logic 103.

Basically, the printer 16 is a computer controlled sequential comparisonsystem wherein the computer program is hard wired logic including amaster read-only-memory (ROM) 105 and a subroutine read-only-memory 107.The read-only-memories 105 and 107 store the program for sequentiallyoperating a comparison network to generate control signals to acharacter printer such as the Suwa Seiko Model EP101-S. Summarily, theread-only-memories 105 and 107 operate as follows: the read-only-memory105 contains the main working program which includes instructions foraddressing the read-only memory 107 to select a subroutine storedtherein. Addressing the read-only-memory 105 is accomplished in one ofthree ways: (1) by data stored in the memory itself, (2) by selecting anaddress stored in a jump table located at the last fourteen words of thememory 105, or (3) by incrementing the address register of theread-only-memory 105. The read-only-memory 107 contains the subroutinescalled for by the memory 105 and when so specified by a particularsubroutine, the output of the memory 105 is applied to the data busthrough the ROM 1 output buffer 151. The subroutines of theread-only-memory 107 direct the functions of the printer such asperforming all data transfers into the printer. Such transfers includereading data from the acquisition unit 10 or the lever switches 135including the date switch 52 and the time switch 54. In addition, thesubroutines of the read-only-memory 107 provide instructions for storingdata in a random access memory 109, reading data from the random accessmemory and other functions to complete the printing of hard copy patientlabels 18. Subroutines of the read-only-memory 107 are utilized throughthe use of decoders 111, 113 and 115 which control data lines 117 and119 to the random logic 103.

Inserting an acquisition unit 10 into either the chute 40 or 42 of theprinter 16 interconnects the memory 84 to interface circuitry 121including an input buffer 123 and control lines 125 and 127. The inputbuffer 123 interconnects an acquisition unit to data selector logic 129having an output line coupled to a bus tie-in 131. Also connected to thebus tie-in is a data buffer 133, the lever switches 135, and decodinglogic 137, the latter also connected to the random logic 103. Datatransferred through the bus tie-in 131 is transferred over a line 139connected to comparator logic 141, a random access memory (RAM), addressregister 145, a RAM input register 143 and a read-only-memory addressregister 147.

Various sequencing operations of the printer are controlled byinstructions from the random logic 103 as generated on a line 149 havinginterconnections to the register 145, the data selector 129, and the RAMinput register 143 in addition to terminations at the lines 125 and 127.

As mentioned, sequencing of the operation of the printer is primarilyunder the control of the read-only-memory 105 and secondarily under thecontrol of the read-only-memory 107. Enabling instructions to the memory105 are received through the register 147 and control instructions fromthe memory are coupled through a buffer 151 to a word detector 153 anddata select logic 155. Also coupled to the output buffer 151 is theaddress register 147 for addressing the memory 105 by data storedtherein. Instructions from the read-only-memory 105 for theread-only-memory 107 are coupled through the data select logic 155 to aread-only-memory address register 157. Selected subroutines in thememory 107 provide instructions to the decoders 111, 113 and 115 throughan output register 159.

Control signals to the character printer (not shown) and timing signalsfor operation of the printer are connected to the random logic 103through printer interface logic 163. The logic 163 includes a triggermagnet controller 161 generating energizing signals to individual printhammer solenoids for producing a printing action on the labels 18. Thenumber of trigger magnet controllers 161 depends on the number ofcolumns possible to be printed by the character printer. In addition,the random logic 103 provides a control signal to paper feed logic 167providing a voltage for controlling the movement of the labels 18 pastthe character printer. Timing signals generated by the character printerare applied to shaping circuits 169 to provide clock signals to therandom logic 103 to synchronize the operation of the comparison systemwith the actual printing operation.

A clock 171 provides a primary clock for the printer through the randomlogic 103. Since the printer 16 is synchronized with the operation ofthe acquisition unit 10, the random logic 103 provides control signalsto the clock 171.

Referring to FIG. 7, the printer 16 remains in an idle mode until anacquisition unit is inserted into either chute 40 or 42 therebycompleting a connection between the acquisition unit 10 and theinterface 121. Initially, the printer, through instructions from thememory 105, sequences to step 173 to check the condition of a statusregister located in decoding logic 137 to determine if the acquisitionunit 10 is inserted into either chute 40 or 42 and the associated PRINTbutton has been pressed. If inquiry 173 produces a positive response,the printer advances to step 183 where system registers are initializedand the contents of the status register of random logic 103 modified sothat subsequent inquiry 175 also results in a positive response. To testthe condition of the status register, ROM 105 addresses ROM 107 to causea comparison of a code in the register 143 with the code stored in thestatus register. This is completed by a subroutine of ROM 107transferring a code from ROM 105 to the register 143 which is thencompared in a comparator 141 with the code from the status register ofrandom logic 103.

After the PRINT button has been actuated, the PAUSE button is enabled.If this button is actuated, the printer completes printing of anypartially printed label and then cycles through inquiry steps 173 and175. Actuating the CONTINUE button sets the status register of therandom logic 103 such that inquiry 173 produces a negative response butinquiry 175 produces a positive response. Actuating the same PRINTbutton sets the status register of random logic 103 such that inquiry175 produces a negative response but inquiry 173 produces a positiveresponse, sequencing the printer through step 183 which results in apositive response to inquiry 175.

A positive response to the inquiry 175 then advances the printeroperation to a step 185 wherein the ID counters are set. The printerlogic scans the memory 84 for the start of data (SOD) code at a step187. Upon detecting the start of data code the printer advances to astep 195 where it waits for an IDA code to appear, thereupon advancingto a step 197. Step 197 increments the IDA counters. When the ID datafor one patient appears at the input buffer 123, the ROM 105 calls asubroutine from the ROM 107 to increment the patient ID counters. Thecontents of patient ID counters are compared with the contents of thepatient ID registers in inquiry steps 201 and 203. If either inquiry 201and 203 produce a negative response, indicating the patient ID registerand patient ID counters do not contain the same bit pattern, the printersequences back to inquiry step 195 to wait for the next ID mode word.

If both 201 and 203 produce a positive response the printer advancesthrough a data storing step 207, an inquiry 209, a second data storingstep 211 and an inquiry 213. During this sequence the patient ID isstored in the random-access-memory 109.

Upon completion of the inquiry 209 or 213 with a negative response, thememory 105 advances the printer into a sequence of inquiries 215, 217and 219. If there is no external device data associated with the presentpatient, the sequence of operation advances through inquiries 215 and217 to inquiry 219. The conditions of a negative response to the inquiry215 or a positive response to the inquiry 217 will be discussed shortly.A positive response to the inquiry 219 advances the printer operation tostep 227 wherein a register is set to denote the case of ID datafollowed immediately by note data. Upon completion of step 227, theprinter sequences to a step 225 wherein the note data is placed in atemporary storage area in the RAM 109. The data storage step 225 mayalso be entered through step 223 any time a note mode word has beendetected in the patient's data. When the printer operation has advancedto step 225, the patient ID has been stored in the RAM 109 and note datafrom memory 84 is transferred to the RAM 109 through the register 143.All data transferred from the memory 84 to the RAM 109 is transferred atthe clock frequency of the acquisition unit 10.

A negative response to the inquiry 219 advances the printer operation tostep 221 and the ROM 105 is addressed with operating instructions fromthe jump table. In step 221 the current data mode word is used to selectan address from a jump table in ROM 105 for the purpose of causing abranch in the sequence to the step appropriate for processing the typeof data indicated by the mode word. From step 221, a jump may be made toany of steps 281, 283, 291, 303, 319, 337, 353, or 355. Results of thesejumps will be discussed.

Upon completion of the load data step 225, the sequence advances to aninquiry 229 and upon a negative response to inquiries 231 and 233 to astep 235. After completing the step 235, the printer operation advancesto an inquiry 237 of FIG. 7b.

The inquiry 237 is also entered if the inquiry 215 produces a negativeresponse. If the inquiry 215 produces a positive response and theinquiry 217 results in a positive response, then a register incrementingstep 239 is entered and upon completion of this step the sequence movesto inquiry 237.

Still another sequence for entering the inquiry 237 is through a step241 any time an external or external manual mode word is detected in thepatient's data. Still another path for entering the inquiry 237 is whenthe inquiry 229 produces a positive response indicating that a word fromthe acquisition unit 10 is an external or external manual mode wordwhereupon the inquiry 243 is made. A negative response to the inquiry243 enters the inquiry 237 directly and a positive response advances thesequence to a step 245 and through the step 239 to the inquiry 237.

If the word transferred from the memory 84 is identified as an externalmanual mode word, the sequence advances to a store data step 247 whereinthe word from the memory 84 is transferred to the register 143 forstorage in the RAM 109. Upon completion of the step 247, the sequenceadvances to an inquiry 251. A positive response to inquiry 251 advancesthe printer to a register incrementing step 253 which is the same asstep 239. Following the step 253, a label stop code is loaded into theRAM 109 in a step 255 and then, a line stop code and column stop codeare loaded into the memory 109 in a step 257. A column stop codeindicates that all characters on the present row of the print drum whichare to be printed on the current line of the label have been printed. Aline stop code indicates that all characters to appear on one line ofthe label have been printed. A label stop code indicates that an entirelabel has been printed. Also during the step 257, the RAM input register143 is cleared, whereupon the sequence advances to a step 261. Step 261loads the trigger magnets controller 161. Following the step 261 aninquiry 263 is made to determine if the accessed address in the RAM 109contains a column stop code. If not, the printer cycles from step 263 toinquiry 261 until all characters on the present drum row which are toappear on the current label line have been printed. This is indicated bythe detection of a column stop code. The printer 16 then advances to aninquiry 259 wherein the RAM input register 143 is incremented and testedfor the presence of a line stop code which would indicate that allcharacters on the present line of the label have been printed. Untilthis code is detected the printer cycles from inquiry 259 to step 261until each row on the print drum has passed and the line stop code isdetected. The printer then advances to inquiry 265 wherein the presenceof the label stop code is tested. If not present, the printer cycles tostep 257 to print additional lines of data until inquiry 265 detects thelabel stop code indicating that the entire label has been printed. Theprinter then advances to step 267 wherein the next label 18 in the stripis advanced until it enters the printer mechanism. The RAM is thencleared of patient data in step 269 and the sequence then returns toinquiry 175.

Returning to the inquiry 237, if the word under consideration in thememory 84 is not an external manual mode word, the sequence advances toan inquiry 271 (instead of the step 247) and upon a positive responsethereto continues to the inquiry 251 and therefrom as explained. Anegative response to the inquiry 271 advances the sequence to an inquiry273 which returns the sequence to the load data step 225 upon a positiveresponse and advances the sequence to an inquiry 275 from a negativeresponse. A positive response to the inquiry 275 indicates that the wordnext to be transferred from the memory 84 is the end-of-data word andthe sequence advances to a step 277 to set the status flip-flop and thesequence advances to an incrementing step 279. The step 279 incrementsthe IDA registers. This step is also entered through a step 281 when anIDA mode word is detected.

The steps 277 and 279 are also completed any time an end-of-data modeword is used to address the read-only-memory 105 jump table.

Referring to FIG. 7c, a negative response to the inquiry 251 advancesthe printer sequence to an inquiry 285 and upon a positive responsethereto advances to an inquiry 287 and then to an asterisk code storingstep 289. The step 289 is also entered from a step 291 when the word tobe transferred from the memory 84 is manually entered temperature data.The step 289 stores an asterisk code in the RAM 109 for printing on alabel 18 to highlight manually generated data.

Following completion of the step 289, the printer sequence advances to adata storing step 293 wherein an inquiry of the content of the externalregister is made. The step 293 may also be entered from a step 303 whena temperature mode word is detected at the memory 84. A positiveresponse to the inquiry of step 293 advances the printer to a datastoring step 299 and then to a step 301. The step 301 is a step forloading the RAM 109 with data from an acquisition unit.

A negative response to the inquiry 285 sequences the printer to aninquiry 305 which again checks the condition of the external register.Following a negative response to the inquiry 305, the sequence advancesthrough an inquiry 307 and then to a data storing step 315 eitherdirectly or through an asterisk data storing step 317. The step 317 forstoring an asterisk code in the RAM 109 may also be entered through astep 319 if a respiration rate manual mode word is detected in thememory 84. In the step 315, data transferred from the memory 84 isstored in the RAM 109. This step is also entered from a step 337 when arespiration rate mode word is detected in the memory 84. Step 315 iscompleted by using the next mode word in the memory 84 to address theROM 105 jump table to branch in accordance with the mode word.

A positive response to the inquiry 305 sequences the printer routine toan inquiry 339 and from the inquiry 339 directly to a data storing step349 or through an asterisk code storing step 351. The asterisk codestoring step 351 may also be entered from the step 353 when a pulse ratemanual mode word is detected in the memory 84. The data storing step 349is also entered from the step 355 when the pulse rate mode word isdetected in the memory 84.

Primarily, data is stored in the RAM 109 from the acquisition unit 10 inthe steps 301, 315 and 349. When manually generated data for thetemperature, pulse rate and respiration rate are stored in the memory84, an asterisk code is stored in the RAM 109 in the steps 289, 317 or351.

Upon completion of the transfer of data from the acquisition unit 10into the RAM 109, the print routine is entered. During the printroutine, the printing mechanism sends three signals to the controlcircuitry. These are denoted as the printer reset signal and the TP andTL signals. The reset signal occurs once for each complete drumrevolution of the printing mechanism and the TP and TL signals occur foreach row of characters on the print drum. In a typical embodiment of theprinter mechanism there are sixteen rows of characters with eachcharacter identified by a code signifying its row and column location onthe print drum. The TP signal occurs prior to the row it is associatedwith and the TL signal occurs at the end of the row with which it isassociated. Actual printing of a character is completed by activatingtrigger magnets to drive a hammer against the print drum, causing thecharacter in that row and column location on the print drum to beprinted on the label 18. The trigger magnets are activated on the TPsignal and deactivated on the TL signal.

Printing of a character is completed by transferring to the RAM inputregister 143 the code for a character at a particular row and columnlocation and comparing the number in the register 143 with the datastored in the RAM 109, the comparison taking place in the comparator141. Thus, the register 143 contains the code of the print drum linewhich will next be struck by the printer hammers (that is, the line onwhich the next set of characters to be printed is located). The printdrum is constructed such that the data stored in the RAM 109, when thesame as the print drum line code, is the correct character to beprinted.

A character is printed by shifting a logic ONE signal into a twenty bitserial input, parallel output shift register in the trigger magnetscontroller 161. If the code at a particular address in the RAM 109 andthe code in the register 143 are the same, a logic ONE is shifted intothe shift registers. If the codes are different, a logic ZERO is shiftedand the hammer magnets remain deactivated. Each shift register outputcontrols a trigger magnet driver which is switched on when the shiftregister output goes to logic ONE.

As an example, assume the data to be printed is T102.5* starting incolumn one on the label 18. Starting at line zero on the print drum, theshift registers of the trigger magnets controller 161 will contain alllogic ZEROES with the exception of a logic ONE in column 3 which willcause the number 0 to be printed on the label 18. This is because thenumber stored in the third location of the RAM 109 contained a coderepresenting the number 0 in the data T102.5*. Next, the register 143 isincremented to a code representing the number 1. When the secondlocation in the RAM 109 is compared to the contents of the register 143in the comparator 141, a match will result and a logic ONE will beshifted into the trigger magnets controller 161 thereby causing thenumber 1 to be printed in column 2 on the label 18. This sequencecontinues with codes representing the numbers 2-9 and other charactersshifted into the register 143 and compared with the various locations ofthe RAM 109. When the code representing the letter T is shifted into theRAM input register 143, a match is made in column one since the code forthe letter T is now in the register 143. Thus, a logic ONE will beshifted into column one of the trigger magnets controller 161 to controlthe appropriate trigger magnet causing the letter T to be printed incolunn one of the label 18. The other characters are printed in asimilar manner as is the asterisk.

After completely printing the data for a particular patient ID, the nextlabel is incremented under the print drum, the printer sequences toinquiry 175, and data for the next patient ID is printed on the label18. This continues for each patient ID until all the data transferredfrom the acquisition unit 10 to the RAM 109 is printed on a label 18.Following the printing of data for the last patient ID, the printsequence returns to the idle mode.

If during the operation of a printing sequence the label supply isdepleted or a malfunction occurs in the print mechanism, the printer maybe halted by use of the PAUSE button to await further instructions toproceed. When reactivated with the CONTINUE button, the sequence ofprinting begins where previously terminated. If during this shut downanother acquisition unit is inserted into the printer, the data thereincannot be read into the RAM 109 until the data in the previouslyinserted acquisition unit has been printed on the labels 18.

Following completion of the printing of all the data in a particularacquisition unit, and upon its removal from the chute 40 or 42, thememory 84 is cleared except for a start-of-data word at one location andan end-of-data word at the next location. The acquisition unit is thenready to be used again for acquiring and storing additional temperature,pulse rate, and respiration rate data from patients up to the limit ofthe memory 84.

While only one embodiment of the invention, together with modificationsthereof, has been described in detail herein and shown in theaccompanying drawings, it will be evident that various furthermodifications are possible without departing from the scope of theinvention.

What is claimed is:
 1. In a medical data acquisition and storage system,comprising in combination:display means for providing a visualpresentation of input medical data, at least one data input means foraccepting externally generated data, a display register for receivingand holding externally generated data to be presented at said displaymeans, first means for gating data from each of said input means to saiddisplay register, manual input means for generating input data to begated to said display register, memory means having multiple addresslocations for storing data holding in said display register, secondmeans for gating the data holding in said display register into saidmemory means for retention therein, a state controller connected to saidmeans for gating for establishing the order of data gated to saiddisplay register from all of said input means, record means foractuating said second means for gating to transfer data from saiddisplay register to said memory means, memory control means responsiveto the transfer of data from said display register to said memory meansto actuate said state controller to advance the sequence of ordered datagated to the display register, and repeat means for actuating said statecontroller to repeat the gating of input data into said display registerfrom the input means previously gated thereto.
 2. A medical dataacquisition and storage system as set forth in claim 1 wherein saidstate controller includes means for establishing the order of data gatedfrom said display register into said memory means.
 3. A medical dataacquisition and storage system as set forth in claim 1 wherein saiddisplay means further includes display control means responsive to saidstate controller and connected to said display register to select eitherdata from the data input means or the manual input means for visualpresentation.
 4. A medical data acquisition and storage system as setforth in claim 1 wherein said state controller advances the sequence ofordered data gated to said display means in response to a transfer ofdata into said memory means.
 5. A medical data acquisition and storagesystem as set forth in claim 1 wherein said state controller includesmeans responsive to an externally generated signal to activate thesystem from an idle mode to a data receiving mode.
 6. A medical dataacquisition and storage system as set forth in claim 1 including clockmeans for generating system clock pulses to establish the timinginterval between data transferred within the system.
 7. A medical dataacquisition and storage system as set forth in claim 6 including meansfor sensing the condition of a power supply to initially shut down thesystem to a first threshold condition and to completely shut down thesystem at a second threshold condition.
 8. A medical data acquisitionand storage system, comprising in combination:display means forproviding a visual presentation of input medical data, temperature inputmeans responsive to externally generated temperature related data andproviding a system signal varying with the externally generated data,respiration rate input means responsive to externally generatedrespiration rate related data and providing a system signal varying withthe externally generated data, pulse rate input means responsive toexternally generated pulse rate data and providing a system signalvarying with the externally generated data, manual input means forgenerating a system signal including an I.D. code to be visuallypresented on said display means, a display register for receiving andholding the system signals to be presented at said display means, meansfor gating each of the system signals in sequence to said displayregister, memory means having multiple address locations for storingsystem signals visually presented in said display means, means fortransferring the signals holding in said display register into saidmemory means for retention therein; a state controller connected to saidmeans for gating for establishing the order of signals gated to saiddisplay register for all of said input means, record means for actuatingsaid means for transferring to transfer data from said display registerto said memory means, memory control means responsive to the transfer ofdata from said display register to said memory means to actuate saidstate controller to advance the sequence of system signals gated to thedisplay register, and repeat means for actuating the said statecontroller to repeat the gating of system signals into said displayregister from the input means previously gated thereto.
 9. A medicaldata acquisition and storage system as set forth in claim 8 includingclock means for generating system clock pulses.
 10. A medical dataacquisition and storage system as set forth in claim 9 wherein saidtemperature input means includes means responsive to a frequency varyingwith the temperature related data and providing a pulse train as thesystem signal.
 11. A medical data acquisition and storage system as setforth in claim 10 wherein said means responsive to a frequency varyingwith the temperature related data includes counting means receiving thetemperature related frequency data and triggered into an "on" state byone clock pulse and to an "off" state by a subsequent clock pulse andwhere the total count registered represents the system signal.
 12. Amedical data acquisition and storage system as set forth in claim 9wherein said respiration rate input means includes counting meansreceiving the clock pulses and triggered to an "on" state and an "off"state by the externally generated respiration rate data and where thetotal count registered represents the system signal.
 13. A medical dataacquisition and storage system as set forth in claim 12 wherein saidrespiration rate input means further includes means for dividing a fixedfactor by the total count registered to normalize the system signal. 14.A medical data acquisition and storage system as set forth in claim 9wherein said pulse rate input means includes counting means receivingthe clock pulses and triggered into an "on" state and "off" state by theexternally generated pulse rate data and where the total countregistered represents the system signal.
 15. A medical data acquisitionand storage system as set forth in claim 14 wherein said pulse rateinput means includes means for dividing a fixed factor by the totalcount registered to normalize the system signal.
 16. A medical dataprinter for receiving data from a portable data acquisition means havingstored therein a quantity of medical data, comprising incombination:memory means for storing a quantity of medical data from theacquisition means, transfer means for gating the medical data from saidacquisition means to said memory means, display means including aprinter of multiple characters, said display means including means forstoring each character as identified by an identifying code, means forcomparing each identifying code with the stored medical data in saidmemory means and generating a print signal upon a predeterminedcomparison condition, means responsive to the print signal to actuatesaid printer to cause a preselected character, representative of themedical data, to be printed; and control means for sequentially shiftingeach identifying code and each entry of medical data from said memorymeans to said means for comparing.
 17. A medical data printer system asset forth in claim 16 wherein said print includes a character printerwith a character print controller responsive to the print signals foractuating preselected characters for printing thereof on a hard copy.18. A medical data printer system as set forth in claim 17 wherein saidcontrol means includes a first read-only memory storing a first set ofoperating instructions for said control means and a second read-onlymemory storing a second set of operating instructions for said controlmeans.
 19. A medical data printer system as set forth in claim 18including means connected to the output of the first read-only memoryfor providing sequence instructions thereto at the inputs thereof.
 20. Amedical data printer system as set forth in claim 16 wherein said memorymeans includes a random access memory having storage locations for eachentry of medical data transferred from said acquisition means.
 21. Amedical data printer system as set forth in claim 20 wherein said meansfor comparing includes a register for temporarily storing eachidentifying code to be compared with the stored entries of medical datain said random access memory.
 22. A medical data printer system as setforth in claim 21 including external control means for selecting one ofa plurality of acquisition means having stored multiple entries ofmedical data for transferring to said random access memory.
 23. Amedical data printer system as set forth in claim 22 including date andtime switches for generating date and time data for comparison with theidentifying codes for presentation at said display means.
 24. A medicaldata acquisition and display system as set forth in claim 16 whereinsaid control means includes means for controlling said transfer means togate in additional medical data entries from said acquisition means tosaid memory means after each identifying code has been compared withpreviously stored data in said memory means.
 25. A medical dataacquisition and display system as set forth in claim 24 includingclearing means responsive to the last entry of medical data in saidacquisition means for presetting said acquisition means to clear themedical data stored therein.
 26. A medical data acquisition and displaysystem as set forth in claim 16 wherein said control means responds to astart-of-data signal from said acquisition means to control saidtransfer means to gate a first quantity of medical data to said memorymeans.
 27. A medical data acquisition and display system as set forth inclaiim 16 wherein said control means includes a first read-only-memorystoring a first set of operating instructions for said control means,and a second read-only-memory storing a second set of operatinginstructions for said control means.
 28. A medical data acquisition anddisplay system as set forth in claim 27 wherein the secondread-only-memory receives operating instructions from the firstread-only-memory.
 29. A medical data acquisition and display system asset forth in claim 27 wherein the second read-only-memory includesaddress locations each containing a particular identifying code.
 30. Amedical data acquistion and storage system, comprising incombination:display means for providing a visual presentation of inputmedical data, at least one data input means for accepting externallygenerated data, a display register for receiving and holding externallygenerated data to be presented at said display means, first means forgating each of said input means to said display register, memory meanshaving multiple address locations for storing data visually presented tosaid display means, second means for gating the data holding in saiddisplay register into said memory means for retention therein, a statecontroller connected to said means for gating for establishing the orderof data gated to said display register from all of said input means,record means for actuating said second means for gating to transfer datafrom said display register to said memory means, memory control meansresponsive to the transfer of data from said display register to saidmemory means to actuate said state controller to advance the sequence ofordered data gated to the display register, and repeat means foractuating said state controller to repeat the gating of input data intosaid display register from the input means previously gated thereto. 31.A medical data acquisition and storage system as set forth in claim 30including a temperature data generator, a respiration rate datagenerator, and a pulse rate data generator for providing the externallygenerated data.
 32. A medical data acquisition and storage system as setforth in claim 31 wherein said state controller first sequences thegating of pulse rate data to said display register, next sequences thegating of temperature data to said display register and then sequencesthe gating of respiration rate data to said display register.
 33. Amedical data acquisition and storage system as set forth in claim 31including a temperature counter connected to said temperature datagenerator for converting an analog output thereof into binary coded datato be gated to said display means.
 34. A medical data acquisition andstorage system as set forth in claim 31 including a respiration ratecounter connected to said respiration rate generator for converting theanalog output thereof into binary coded data to be gated to said displaymeans.
 35. A medical data acquisition and storage system as set forth inclaim 31 including a pulse rate counter connected to said pulse rategenerator for converting the analog output thereof into binary codeddata to be gated to said display means.
 36. A medical data acquisitionand storage system, comprising in combination:display means forproviding a visual presentation of input medical data; temperature,respiration rate and pulse rate input means for generating temperaturerelated input data, respiration rate related input data and pulse raterelated input data; manual input means for generating input dataincluding an I.D. code to be associated with selected input data; firstmeans for gating the I.D. code and input data to said display means tovisually present the generated data; memory means having multipleaddress locations for storing an I.D. code and input data associatedtherewith after visually presented in said display means; second meansfor gating the data after being visually presented in said display meansto an address location of said memory means for retention therein; astate controller connected to said first means for gating to establishthe order of input data gated to said display means; record means foractuating said second means for gating to transfer data from saiddisplay means to said memory means; memory control means responsive tothe transfer of data from said display means to said memory means toactuate said state controller to advance the sequence of ordered datagated to the display means; and repeat means for actuating said statecontroller to repeat the gating of input data into said display meansfrom the input means previously gated thereto.
 37. A medical dataacquisition and storage system as set forth in claim 36 wherein saidstate controller includes means for recycling in an ID mode to enablestoring in said memory means a particular ID data length.
 38. A medicaldata acquisition and storage system as set forth in claim 36 whereinsaid display includes light emitting diodes arranged for alphanumericpresentation, and further including a data multiplexer coupled to saidmeans for gating to convert the input data into signals for driving thelight emitting diodes.
 39. A medical data acquisition and storage systemas set forth in claim 36 wherein said pulse rate input means includes apulse probe sensor for generating a probe interconnection signal to thestate controller.
 40. A medical data acquisition and storage system asset forth in claim 36 wherein said temperature input means includes atemperature probe sensor for generating a probe interconnection signalto said state controller.
 41. A remote date acquisition and storagesystem as set forth in claim 36 including an indicator for presenting asystem ready signal to an operator prior to actuating said manuallyinput means to generate an I.D. code.
 42. A medical data acquisition andstorage system as set forth in claim 36 wherein said temperature relatedinput data, respiration rate related input data and pulse rate relatedinput data is generated simultaneously and sequentially transferred tosaid display means in the order of pulse rate related input data,temperature related input data and respiration rate related input data.43. A remote data acquisition and storage system as set forth in claim36 including means for rejecting initial pulse rate related input datato permit system stabilization.
 44. A medical data acquisition andstorage system as set forth in claim 43 including means for rejectinginitial respiration rate related input data to permit systemstabilization.
 45. A medical data acquisition and storage system as setforth in claim 36 including means for displaying pulse beat to indicateto an operator a system ready condition prior to actuating said manualinput means to generate an I.D. code.
 46. A method of acquiring andstoring medical data in a portable unit, comprising the stepsof:generating input data, including temperature related input data,respiration rate related input data and pulse rate related input data,and an I.D. code to identify certain selected input data; sequentiallygating the generated input data to a display for providing a visualpresentation of the input data; actuating record means for gating thedata visually presented into a storage means having multiple addresslocations wherein the I.D. code is stored at address locations withassociated input data; establishing the order of data gated to thedisplay; and advancing the sequence of the established order of datagated to the display in response to the transfer of data from thedisplay to the memory.
 47. A method of acquiring and storing medicaldata as set forth in claim 46 wherein the input data is gated fordisplay sequentially in the order of the I.D. code for associated datafollowed by pulse rate related input data, temperature related inputdata and respiration rate related input data.
 48. A method of acquiringand storing medical data as set forth in claim 47 including the step ofgenerating a pulse beat display to indicate a system ready condition.49. A method of acquiring and storing medical data as set forth in claim46 including the step of generating a code indicator for signifyinggenerated additional input data.
 50. A method of acquiring and storingmedical data as set forth in claim 46 including the step of sensing thecondition of a system power supply to initially shut down the system ata first threshold condition and to completely shut down the system at asecond threshold condition.